Vulcanizing apparatus



Nov. 22, 1949 D. G. REMPEL 2,488,935

VULCANI Z ING APPARATUS Filed Aug. 26, 1944 5 Sheets-Sheet l @PTH/T 2727v Dierich GnRempel BY i s. ,6M

Htomey Nov. 22, 1949 D. G. REMPEL VULCANIZING APPARATUS 5 Sheets-Shea?I2 Filed Aug. 26, 1944 l Mw n, Tm n me, Y VR w w. Mm .mx ...L Ul ww WNov. 22, 1949 D. Gy. REMPEL VULCANIZING APPARATUS 5 Sheets-Sheet 5 FiledAug. 26, 1944 nvmvroze.r Dietrich G. Rempel BY MMM; I Horney Nov. 22,1949 D. G. REMPEL 2,488,935

VULCANIZ ING APPARATUS Filed Aug. 26, 1944 5 Sheets-Sheet 4 INVENTOR. l

Dierch @Hempel BY U11-1m. md

momey Nov. 22, 1949 D. G. REMPEL v'ULcANI z ING APPARATUS Filed Aug. 26,1944 5 Sheets-Sheet 5 'HIT x01 "Illas: l

BY (ALUM. MJ

Horney Patented Nov. 22, 1949 VULCANIZIN G APPARATUS Dietrich GJ .RempehAkron, hio,.assignor to The Sun Rubber Company, Barherton, Ohio,v aco1'.-

poration oiOhioY Appucauwaugust 26, 1944,. seriar iva-551,279

(cl. 12s- 17) 7 Claims.

This invention relates to vulcanzing or like article-forming apparatus,vand in particular relates to vulcanizing molds.

One object of the invention is to provide Han improved sectional mold ofvunitary construction adapted to be supported between relatively movablepress members, with self-'contained means provided in the mold unit tobe self-operating with relative movement of. the mold sections to shiftrelatively shiftable parts ofan article-form'- ing core member, therebyfacilitating breaking articles from the core members for ready removalofV the same, and greatly reducing the operational change cycles.

Another-.object of the inventionis to provide apparatus of the characterdescribed` in which a part of the core member is removable from the moldwith a formed article retained thereon; with a consequent saving of timeand labor `due to the fact that while the article is being stripped-fromsaid removed core part a separate similar core part may be substitutedfor a subsequent articleforming operationof the mold.

Another object of the invention is to provide an improved coreconstruction in apparatus of the character described', by which it isonly necessary to remove a relatively small part of the-core in order toremove an article formed in thefmol'd, thereby materially reducing theWeight of parts required to be handled by the operator during eacharticle-forming cycle, and alsom-inimizing wear and tear and maintenanceon ther mold.

Still another object of the invention is' to'provide in apparatus ofthecharacter `described improved means automatically operable, jointly'or separately, as desired, to move primary andfsecondary core membersv-to intermediate positions between the mold sections in an openposition thereof.

Still another object of the invention is to provide in apparatus of thecharacter described secondary core means, as described abovabywhic'h aplurality of secondary cores may be removed from the mold as aunit, withimproved .means provided to permit placement of the secondary coremembers in the lower mold section without interfering with theautomatic'mea-ns` for positioning the core members in the intermediateposition thereof.

These and other objects of the invention will be manifest from thefollowing brief description and the accompanying drawings.

Of the accompanying drawings.:

Figure 1 is a frontv elevation, partly broken away, of a platen presshaving therein a mold 2 embodying g thelnvention, the press beingclosed.

Figure 2 -is a vfragmentary view, on. a greatly enlarged scale,asv-viewed. substantially at line 2-2.in Figure 1:,. at the` centerportion of the press.

Figure. 3 is a cross-section',A on a. largerA scale than Figure. 1,taken substantially on line 3 3 of Figure 2.

Figure 4 is. an enlargedcross-section taken substantially on line 4-4 inFigure 1.

Figure 5 isY aview similar to Figurev 4, but illustrating .the moldin.vfully open position.

Figure. 6 is adetail view of a. secondary core removed from the mold.

Figure '7 is a plan view. of the core supporting frame for the coremembers, as viewed on line '1 -'I of Figure 5.

Figure 8 is a front elevation, corresponding to Figure 1, illustratingva modified form of mold embodying the invention. Y

Figure 9 is a side elevation, partly lbroken away and in section, .as`viewed fromv either side of Figure -8.v

Figure I()V is a view similar to Figure 9, but illustrating the mold invfully open position.

Figure 1I is av fragmentary cross-section taken online I l--II of`Figure 9;

Referring particularly to Figures 1 to '7 of the drawings, the numeralI5 designates ak unitary cavity mold construction havingiself-containedautomatic featuresv embodying the invention herein, as will belsubsequentlydescribed. Mold I5 vhas upper and lower mold: sections I5and I'I, respectively; adapted to be in mating or reg'- isteringrelation when the mold is closed. Upper m'oldsection I E may" bereleasabl-y secured, as by means of clamps I8, I 8, to an upper AplatenI9 secured to a xed head I994 of a hydraulic platen press 20' of knowntype (see Figure l), while the lower mold section I1' may be similarlysecured, by clamps 2|, 2I`, tov a lower platen 22 carried by across-member 23 which isv vertically movable ori-'gui'desll 24 by vavhydraulic ram 25. The'iplatens YI9and- '22 may be heated by meansof-steam orother medium, from a suitable source, to heat the -mold'sections for vulcauizing operations tovbe- Vdescribed later.

The present improvements may be incorporated into afsingle-cavity typemold, but for the purposes of illustrating vthe invention' a multipletype mold will be described. Accordingly, the mold I5 may comprise twospacedrows of relatively small cavity molds |58, I5a, the upper andlower halves or sections IBL.' I6a and Ila, I 'Ia of which are securedby suitable means '(not shown) to upper and lower mold plates 21 and 28,respectively, which in turn are secured to the press platens i9 and 22by the forementioned clamps i8 and 2l engaging over the edges of saidplates.

Mounted in the space 29 between the two rows of molds la may be a oatingcore-supporting frame 30, comprising vertically spaced bars 3! and 32,between which are clamped, by means of bolts 33, two oppositely disposedseries of horizontally extending core members 3s, 34 having portions 35thereof receivablein mating recesses 36, 36 in the mold halves 16a, andila for accurately supporting or mounting the core memn bers between thesame in the closed position of mold I5, as best shown in'Figure 4. Inthis closed position primary article-forming cores Si of core members 34extend freely into the small molds to be positioned in spaced relationto correspondingly shaped cavity portions 38 thereof.

Secondary cores 4U, 4t (see Figure 6) may be removably mounted inassociation with the primary cores 3l to be in spaced relation tocorrespondingly shaped cavity portions 35 of the mold. To this end,secondary cores 40 may have stems 4l horizontally slidable in bores 42in core members 34, relative rotation being prevented by keys 43 in thecore members 34', being slidably received in keyways 44 provided instems 4i, as shown in Figures 4 and 5. By means of these separableprimary and secondary cores, rubber or like articles, such as the doublechambered, suction-type drain cleaner illustrated in the drawings, maybe readily removed from the molds, as will be described.

To facilitate operational loading' and unloading of the mold, supportingmeans having a lostmotion action is provided to retain the cores in anintermediate position between the mold sections when the mold is fullyopen, as best shown in Figure 5. For this purpose bars 46, 46 may besecured to opposite ends of the top bar 3i of floating support 36, toextend freely along opposite sides of the mold in horizontal direction.Each bar 46 is provided with spaced apertures 4l for vertically slidablyreceiving depending pins 48, 48 threaded into top mold plate I9, heads49 on the lower ends of the pins being engageable in recesses 50 in thebottom sides of bars 46 to retain supporting frame 30 and the corescarried thereby in said intermediate position in the fully open positionof the mold (Fig. 5). The recesses 5B are provided to permit maximumrelative movement of the mold sections without affecting the unitaryconstruction of the mold, or the selfcontained automatic featuresthereof, just described. Thus, opening movement of the mold is utilizedautomatically to move the cores to the intermediate position, the samebeing carried downwardly with the lower mold by gravity during theinitial opening movement, until-bars i6 engage heads 4S of pins 48.Conversely, when the lower mold section is moved toward closed positionit will pick up the core supporting frame 3d at about the half-way pointof movement and carry it to the fully closed position. v

For automatically shifting the secondary cores 40 to break articles A,vulcanized Ain molds la, away from primary cores 3l cam members 5i, 5i,one for each pair of oppositely disposed molds lia, are pivoted at 52 onsuitable bearings in recesses in bottom mold plate 2B to be swingabletoward one side of the mold, these cams being normally held in freeupright position by means of a spring 53, between each cam and a fixedblock 54 on said bottom plate, yieldingly to urge a stop member 56 onthe opposite side of the cam against the bottom plate. Suitableapertures 30, 3S*i are provided up through frame 3U to permit passagefor cam 5l as the frame is moved vertically. Projecting or off-setportions Ela, 5Ia at the upper portions of opposite edges of cam members5i are engageable with beveled end portions 4W of oppositely disposedpins 4l, upon opening movement of the mold sections i5 and Vl, to urgethe secondary cores 45 outwardly of the pri mary cores 3l, therebyeffectively to break the article A away from the latter.

The secondary cores 4U may be automatically returned to normal closedposition by closing movement of the mold, by means of beveled uprightcam pins 5l, 5l secured to the bottom mold section, as shown, forengagement with edges of apertures 58, 58 in stems 4l, cooperatingapertures 59, 555 being provided in portions 35 oi core member 34 topermit free movement oi the cam pins in apertures 58. The cam pins 5land cams 5i are so designed and arranged that the second ary cores willnot be so returned until the ends of ins 4i passbelow the projecting camportions a, and the latter cam portions are also so ar'- ranged that thesecondary cores will not be moved outwardly as described untilsuilicient clearance is provided between the same and certain parts ofthe lower mold section.

The top portions of cams 5| are beveled or curved at one side facethereof, as indicated at 5 la in Figure 3, so that as closing movementof the mold is started, said beveled portions 52a will engage sideportions of the projecting pin ends 4la (Figure 4) to move the camsaside against the yielding action of springs 53. When the reducedoff-set portions of the cams are opposite said pin ends the cams will beurged to full upright positions against stops 56, by the springs 53.This action prevents fouling of the cams 5I with the ends of the pinswhen the mold is closed.

The floating frame 30, with its side bars 46 extending forwardly andrearwardly of the mold l5, may be utilized for removably supporting twoseries of cores 65, 60 which may also be termed secondary cores, thesecores being arranged at both the front and rear of the mold for formingsocket members 68a, 60a on the articles A for receiving handles (notshown) therein. Obviously the socket members 6ta, being open only at theouter end, could not be formed by a part provided on secondary core 40,for example. Accordingly, pins Bl, 6l the free ends of which comprisethe cores 66, may be mounted on bars 62, 62 on each of which are spacedend pins 63, 63 adapted to be slidably received in bores 64, 64 inbearing blocks 56, 6E which are suitably secured to the ends of sidebars 45, onthe undersides thereof. The upper and lower molds la, and Ilaare provided with mating recesses E?, 6l with which the cores 35cooperate to form the socket Yportion 6 l, as best shown in Figure 4.

front and rear of the mold, are engageable with core bars 62 as the moldsections are moving to fully closed position, to urge the cores inwardlyto positive accurate positions in the molds Ilia, the cams beingsynchronized with cams 5l so that cores 6E! will move in unison withinward movement of secondary cores 40. When the mold is opened, outwardmovement of the secondary cores 4E, as described above, will urge cores.60 and supporting plates 52 outwardly to corresponding extent (seeFigure 5).

In the operation of the unitary mold described above for vulcanizingarticles A of rubber or like material, the press Zfis operated to lowermovable platen 22 to open position, as shown in Figure 5, and inchain-dotted lines in Figure 3, the core supporting frame 3) (see Figure'7) then being in its convenient intermediate position, as retained bythe heads 49 of pins llengaging side bars 46. In this position baresecondary cores di] are placed by inserting the stems 4| thereof inbores l2 of the primary cores, as far as they will go so that the campins 57 will be certain to engage in openings 58 Vof the stems when themold is subsequently closed. The cores Si) are then placed by insertingpins 63 of plate 62 in thel bores 54 of blocks 5S carried by frame Sil,until the plates engage the outer faces of the blocks. Thus the cores inFigure 5 will be approximately in the relative positions shown in Figure4, when the operator will place pieces of rubber or likeY vulcanizablematerial on top of the cores and in the lower mold cavities asnecessary.

Next, the press l5 is operated tomove platen 22 upwardly toward theclosed position, shown in Figures 1, 2, 3 and 4. In moving towardapproximately a half stroke position, the cams lll and E'i, engagingbars 52 and stems 4|, respectively, urge the secondary cores 46 andsocket cores Si) inwardly to positive location to be accuratelypositioned in the corresponding cavity portions S1 and 3Q of the lowermolds lla, inward. movement of stems ll being permitted by yieldingengagement o cams 5l as previously described. When the lower platen 22moves to said approximate half stroke position the portions 35 of corememf"- bers 3ft are accurately received in recesses Sii of the lowermold sections la, thereby to support frame 3e and associated coreelements for the remainder of the upward stroke. In this manner the moldis self-operating by its closing movement for positively locating thecores for the closed position oi the mold, as best shown in Figure 4.

After the vulcanizing period, during which the articles A formed in themolds are under the infiuence of heat supplied through the steam orotherwise heated platens i9 and 22, the press is operated to move platen22 downwardly. Shortly after the platen starts to move down theprojections 5lEL will engage the beveled projecting'ends lle of stems4l, to break secondary cores @il with articles A thereon, outwardly awayfrom primary cores 3l, the core supporting bars t2 being urged outwardlyat the same time Vby engagement of the ends of the cores til with theiinished articles A. As the platen 22 continues toward fully openposition, core supporting frame 33 is retained by the heads on pins d8in the intermediate position best shown in Figure 5, or in chain-dottedlines in Figure 3.

In the intermediate position of frame 38, the bars S2 with cores diithereon are easily removed, thereby to permit removal of the separatesecondary cores te with the completed articles A thereon. By referenceto Figure 6 it will be readily seen that the articles may easily beflexed to strip them from the cores 40, and the latter operations may beaccomplished along with other operations or'treatments as necessarywhile another set of cores 4B -is being positioned in the molds tostart' another cycle of operation as described above.

It will .be readily seen, therefore, that by means of theseself-contained, self-operating features, only partof thearticle-formingcores are required to be removed from the mold, thereby greatlyvreducing'operating time in various respects, and also Substantiallyreducing handling ofy mold'parts, with resulting reduction inmaintenance costs. By means of this construction, also, it is possibleto manufacture articles of complexnature, such as the articles A shown.Similar apparatus has also been highly successful in the production ofsuch `complex articles as gas masks, high-pressure masks, dustrespirators, etc., and may be utilized for economical production of manyotherarticles ordinarily difficult and expensive to manufacture.

Referring now toY Figures 8 to l1 of the drawings, which illustrate amodied form of the invention, the numeral 'F5 designates a unitary moldsubstantially like mold l5, except for certain differences in theself-operating features thereof.

The mold I5 in general comprises upper and lower mold plates i6 and llof upper and lower mold sections 'i8 and 19, respectively, to whichplaies are secured upper and lower mold halves or sections Se and Si ofa plurality of small cavity molds 82 arranged to be in two spaced rows,as before. Between said rows of molds 82 may be a pair of laterallyextending, vertically spaced bars 83 and B4 between which are clampedoppositely disposed core blocks 36, 8S having cores 8l on the outer endsthereof, recesses 3S, 39 being provided in the mold halves 8l), and 8lfor accurately positioning the cores in mold cavities 9d' in spacedrelation to the surface thereof for forming, for example, asingle-chambered, suction-type drainv cleaner A1.

For retaining the cores 8l in a position intermediate of the upper andlower mold sections 8) and 8l, in the open position shown in Figure 10,hooked members 9| are provided at opposite ends of top bar 83 forengaging cross-members 92 of lll-shaped brackets 93, secured to topplate 'i6 at opposite sides of the mold l5. This lost-motion mechanismis self-operating in substantially the same manner as the lost-motionretaining mechanism previously described in connection with Figures l to7, so that further description thereof is deemed unnecessary.

For forming a handle socket Sill on article A1 separate supportingframes or bars et, et -may be pro-vided, each having a series of corepins 91, 5'! on the free ends of which are socketforming cores adaptedto be positioned in corresponding mating cavity portions 98, 9B in thesmall molds 82. Double-beveled enlargements 99' similar to theenlargements t3 previously described, are provided on core pins 91 forself-positioning the cores t5 when mold I5 closes.

As will be seen by particular reference to Figure 10, it is necessary toprovide means for moving the cores 95 vto an intermediate position atthe same time as cores 8l are so moved, when the mold is opened. Forthis purpose the frames 96' may be provided at opposite ends withlaterally outwardly extending fingers id, l, arranged to` be adjacentthe top of the mold in "closed position thereof, these lingers beingdownwardly engageable with forwardly and rearwardly extended hookedportions Il, of cam plates |62, which are pivoted to supporting plates|03 depending from the sides of upper mold section '18, as illustratedin Figure 10. The hooks lill are arranged closely adjacent the bottom ofthe mold so that maximum movement of the mold may be utilized.

The cam plates |02 are so shaped and arranged that in the closedposition of the mold they are maintained with the hooks IUI thereofextended forwardly and rearwardly, by means of straight sides of guideblocks |04, l, secured to the sides of the lower mold sections, engagingstraight edge portions H35 of the cam plates to hold the same againststop pins IGS on the supporting plates |83 (see Figure 9). At thebeginning of a cycle of operation of the mold, however, the mold halveswill be in the open, spacedapart positions thereof shown in Figure 10,which permits placing the cores 95 of the frames $38 in thecorresponding series of lower mold sections le. Obviously this willpresent the outwardly extended hooks directly in the path of thec-orresponding lingers im] of frame 9B below the same when the moldhalves are relatively moved together. The pivoted cam plates |02 are soproportioned and shaped that upon closing the mold from the openposition thereof shown in Figure 1G, but with the empty cores 95, andtherefore the frames 96, gravitationally supported by the lower moldhalves 19, the ngers Hill of frames 96 will engage the cam hooks IUIfrom below and thereby pivot said plates |02 out of the way, asindicated at the left of Figure 10 in chain-dotted lines. Upon continuedupward movement of frames 95 toward the closed position of the mold, theblocks |04 will engage cam surfaces l t5 of cam plates |02 and swing thecam plates back to the normal positions thereof shown in fuil lines ofFigure 10, and with the succeeding opening movement of the mold thehooks |0I will again be in position below the fingers |00 for subsequentmovement to the intermediate position for supporting frames 96 in theaforementioned intermediate positions (see Figures 8 and 9). This actionpermits the operator to load the cores 95 and supporting frame 96 in thelower mold halves before starting to close the mold, without subsequentfouling of the fingers la with hooks IDI, Pins |05 are also utilized t0limit pivotal movement as shown in chaindotted lines in Figure l0.

The operation of the above-described modified mold construction toproduce rubber articles A1 is substantially as described in connectionwith Figures 1 to 7. The formed articles A1, however, may be removed inseries with the frames 96 by lifting the latter over the hooks IGI whenthevmold is fully open (see Figure 10) Although the frames e8 may bereplaced on the hooks after the articles are removed from cores 95certain advantages may be gained by positioning the cores and frames inthe lower mold halves as described above.

rihus has been provided apparatus which accomplishes the aims as setforth in the stated objects of the invention. lt is pointed out that theunitary construction of the mold, with the self-operating featuresincorporated therein, makes it possible to use the same mold indifferent presses which may be of diierent types, and different moldsmay be quickly interchanged in the same or different presses. It shouldalso .be readily seen that the mold constructions shown CII in thedrawings will operate as described above when opening and closing of themold is accomplished in a press which is operable to raise and lower theupper mold section, rather than the lower mold section.

Modifications of the invention may be resorted to without departing fromthe spirit thereof or the scope of the appended claims.

What is claimed is:

1. Vulcanizing or like article-forming apparatus for use in a pressincluding upper and lower platens, movable in substantial parallelismbetween a closed position and an open spacedapart position, comprising acavity mold unit having upper and lower sections for registry with eachother, attaching means on said upper and lower mold sections forreleasably securing the same to the respective upper and lower platensof the press, one or more article-forming cores in said mold unit, asupporting member for said core or cores, said member and said moldsections having complemental interengaging portions for supporting thecores in article-forming position within the mold cavities in the closedposition of the mold, said supporting member and cores thereby beingadapted to be gravitationally moved by being supported on the lower moldsection with relative movement of the mold sections, and lost-motionmeans at substantially spaced points transversely of the mold unit andincluding elements on said member and said upper mold section arrangedto be automatically interengageable with opening movement of the moldsections to retain said member and core or cores thereon in anintermediate position in which the same are substantially spaced fromboth mold sections in substantial parallelism thereto in the openposition of the mold.

2. Vulcanizing or like article-forming apparatus, comprising a cavitymold having upper and lower mold sections, means for relatively movingsaid mold sections between a closed registering position and an openspaced-apart position, an article-forming core unit, a supporting memberfor said core unit, said member and said mold sections havingcomplemental interengaging portions for supporting said core unit inarticleforming position within the mold cavity in said closed positionof the mold, means operable with opening movement of the mold to retainsaid member and core unit thereon in an intermediate position in whichthe same are substantially spaced from both said mold sections in saidopen position of the mold, said core unit including a part relativelyfixed with respect to said member and a part separably connected to therelatively Xed part, said core unit being of requisite shape to form thedesired article in the mold with an apertured Wall in the article formedby adjoining portions of the core parts, said separable core part beingseparable in said intermediate position of the core unit and member tostrip the formed article from the fixed core part.

3. Apparatus as set forth in claim 2, including cam-actuated shiftingmeans operable with open- 'ing movement of said mold sections toseparate said separable core part to spaced position from the Xed corepart.

4. Apparatus as set forth in claim 2, including cam-actuated shiftingmeans operable with opening movement of said mold sections to separatesaid separable core part from the fixed core part, said separableconnection of said separable core part with respect to said xed corepart being such as to permit complete removal of said separable corepart from the rest of the core unit with the formed article thereon.

5. Vulcanizing or like article-forming apparatus, comprising a cavitymold having upper and lower mold sections, means for relatively movingsaid mold sections between a closed registering position and an openspaced-apart position, an article-forming core, a supporting member forsaid core, said member and said mold sections having interengagingportions for supporting said core in article-forming position within themold cavity in said closed position of the mold, means operable withopening movement of the mold to retain said member and core thereon inan intermediat-e position in which the same are substantially spacedfrom both said mold sections in said open position of the mold, saidcore including adjoining article-forming core parts one of which is tobe separable and removable from the rest of the core to facilitateremoval of a formed article from the core, said core being of requisiteshape to form the desired article in the mold and having peripheraladjoining portions of said core parts in spaced relation to form anapertured separating wall in the article, said separable core partthereby upon removal of the same from the rest of the core also beingremovable from the article through the aperture of the separating wallthereof, and means operable upon closing movement of the mold sectionsto bring said core partstogether to article-forming relation.

6. Vulcanizing or like article-forming apparatus comprising a cavitymold having upper and lower mold sections adapted to be in registry whenthe mold is closed, a supporting member, an article-forming core on saidmember and having a portion extending from the member in directionoutwardly of the mold for article forming cooperation with the moldcavity, said member and core thereon being adapted to be supported bysaid lower mold section when the mold sections are relatively movedvertically, interengageable elements on said upper mold section and onsaid member and interengageable to retain th-e member and core in anintermediate position between the mold sections as the same arerelatively moved apart to an open position, a second core adapted to bereceived in said mold cavity in cooperation with rst-named core andhaving a portion extending outwardly of the mold, a support for saidsecond core attached to said extension thereof, and interengageableportions on said upper mold section and on said support andinterengageable to retain the support and second core thereon in aposition between the mold sections corresponding to the intermediateposition of first-named core as the mold sections are moved to said openposition.

7. Vulcanizing or like article-forming apparatus comprising a cavitymold having upper and lower mold sections `adapted to be in registrywhen the mold is closed, a core adapted to be received in said moldcavity and having a portion extending outwardly of the mold, a supportfor said core attached to said extension thereof, said support and corebeing adapted to be supported by said lower mold member as the moldmembers are relatively moved apart to an open position of the mold,spaced members on said upper mold section, spaced elements on saidsupport to vbe above said spaced members when the mold is closed, saidspaced members and spaced elements being interengageable when the moldis opened to retain said support and the core in an intermediateposition between the mold sections, whereby said support and core areremovable by releasing said spaced elements from said spaced members,said spaced members being shiftably mounted on said upper mold sectionto be shiftable by upward engagement of said support as the moldsections are moved to closed position with said core and said supportsupported by said lower mold section, and means being provided on saidlower mold section for returning said spaced members to normal positionas said mold is closed.

DIETRICH G. REMPEL.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTSv Number Name Date 560,123 Daughty May 12, 18961,101,732 Daughty June 30, 1914 1,321,517 Frederick Nov. 11, 19192,059,387 Nanfeldt Nov. 3, 1936 2,124,529 Lester et al July 26, 19382,142,581 Winegar Jan. 3, 1939 2,269,758 Noronha Jan. 13, 1942 2,325,752Dodge Aug. 3, 1943 2,354,447 Allen July 25, 1944

